Granny flats, sleepouts, and minor dwellings are one of NZ's most popular property investments. Here's what they cost and what's involved in 2026.
Granny Flat Cost NZ 2026
| Type | Typical NZ cost |
|---|---|
| Basic sleepout (no plumbing, 20–30m²) | $35,000–$65,000 |
| Studio / sleepout with bathroom (30–40m²) | $65,000–$120,000 |
| Self-contained minor dwelling (45–60m²) | $120,000–$200,000 |
| Self-contained minor dwelling (60–80m²) | $180,000–$280,000 |
| Prefab / modular unit (supply + install) | $75,000–$160,000 |
| Relocatable home (purchase + relocation) | $45,000–$120,000 |
All prices GST inclusive. Auckland and Wellington at higher end. Prices vary by site conditions, specifications, and whether services (power, water, sewer) need extending.
Types of Granny Flat in NZ
Sleepout (No Plumbing)
A room for sleeping and living, sharing the main house's bathroom and kitchen. No separate plumbing means simpler consent and lower cost. Can be built under a simpler consent pathway.
Self-Contained Minor Dwelling
Has its own kitchen, bathroom, and laundry. Can be legally rented as a separate dwelling. Requires full building consent and must meet NZ Building Code for habitable buildings. Most valuable for rental income.
Prefab / Modular Unit
Factory-built unit delivered to site and craned into position. Faster than site-built. Quality varies — choose a reputable NZ manufacturer. Still requires building consent.
Relocated House
An existing house moved to your site. Lower cost than new build but relocation and foundation costs add up. Good option if you can find a suitable house in your area.
What's Included in the Cost?
The prices above typically include the structure but you should budget separately for:
| Item | Typical additional cost |
|---|---|
| Site preparation / earthworks | $5,000–$25,000 |
| Extending power supply | $3,000–$8,000 |
| Extending water supply | $2,000–$6,000 |
| Sewer / septic connection | $3,000–$15,000 |
| Driveway / path | $3,000–$12,000 |
| Landscaping | $3,000–$15,000 |
| Building consent | $3,000–$10,000 |
Total all-up budget: Add 20–40% to the structure cost to cover site and service costs.
Consent Requirements for Granny Flats in NZ
2023 reform: NZ now allows minor dwellings up to 60m² without resource consent on most residential sites under the NPS-UD (National Policy Statement for Urban Development). Building consent is still required.
Key rules: - Up to 60m² = resource consent exempt in most urban zones - Must still get building consent from your local council - Must comply with NZ Building Code (insulation, weathertightness, services) - Setbacks from boundaries still apply (typically 1–1.5m) - Height restrictions (typically 5m for flat sites)
Check with your local council — rules vary by zone. The 60m² exemption doesn't apply everywhere.
Rental Income Potential
A self-contained minor dwelling can generate:
| Location | Typical weekly rent |
|---|---|
| Auckland (suburban) | $400–$650/week |
| Wellington | $380–$600/week |
| Christchurch | $320–$500/week |
| Regional cities | $250–$420/week |
At $400/week, a granny flat generating $20,800/year provides a strong return on a $150,000 investment — approximately 14% gross yield before costs.
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How much does a granny flat cost in NZ? Basic sleepout: $35,000–$65,000. Self-contained minor dwelling: $120,000–$280,000. Prefab: $75,000–$160,000.
Do I need consent for a granny flat in NZ? Building consent is always required. Resource consent is now exempt for minor dwellings up to 60m² on most urban residential sites under the 2023 NPS-UD reform.
Related: New Home Build Cost NZ | Builders Near You